DESCRIPTION (Adapted from Applicant' Abstract): Research-based drug abuse prevention programs have resulted in substantial reductions in drug use when delivered under rigorous experimental conditions. However, these same programs often achieve only modest effects when disseminated beyond the research environment. It is likely that reductions in program fidelity, the quality of delivery, accounts for this deficit. Prior research has identified the following factors as being potentially important for achieving high levels of fidelity: 1) completeness of implementation, 2) teachers' attitudes toward the program, 3) teachers' prior experience with the program, 4) appropriate teaching skills, 5) conceptual understanding of the basis of the program, and 6) administrative and community support for the program. Additional qualities, 7) the role of the program deliverer and 8) the communication style of the deliverer, are characteristics that may influence program outcomes. To date, these qualities have been studied separately but not simultaneously. This study will examine how these factors contribute to teachers' effectiveness at delivering a drug prevention program.